Generally, a holographic stereogram is e.g. produced with a plurality of images obtained by sequentially capturing an object image from different observation points as original images and sequentially exposing and recording each of the original images as a stripe-shaped or a dot-shaped element hologram onto a single hologram recording medium.
For example, a holographic stereogram is produced by means of a holographic stereogram producing apparatus 200 as shown in FIG. 11A. The holographic stereogram producing apparatus 200 is provided with a laser light source 201 which emits a laser light L201 in which wavelength is formed by a single mode having optimum interference characteristic, a half mirror 202 which divides the emitted laser light L201 into an object light L202 and a reference light L203, optical elements 203, 204, 205, 206, 207 and a display apparatus 208 which constitute an optical system of object light L202, optical elements 209, 210, and 211 which constitute an optical system of the reference light L203, and an electromotive stage 213 which retains or supplies a record medium designed for hologram 212 onto which the object light L202 and the reference light L203 are converged.
The optical system including the object light L202 is constituted by a total reflection mirror 203, a first cylindrical lens 204 which has the object light diffused in one-dimensional direction, a collimator lens 205 which converts the diffused object light L202 into a parallel light, a projection lens 206, and a second cylindrical lens 207 which introduces the object light L202 onto a recording medium 212 designed for hologram 212 in an exposing and recording section P201, which are arranged in order from a light incident side along an optical axle. A liquid crystal panel of transmission type, which is arranged between the collimator lens 205 and the projection lens 206, constitutes the display apparatus 208. The display apparatus 208 displays image data output from an image processing section not shown in the figure.
The optical system including the reference light L203 is constituted by a cylindrical lens 209 which has the object light diffused in one-dimensional direction, a collimator lens 210 which converts the diffused object light L203 into a parallel light, and a total reflection mirror 211 which reflects the object light L202 to introduce the reflected one to a hologram recording medium 212 in an exposing and recording section P201, which are arranged in order from a light incident side along an optical axle.
A record medium designed for hologram 212 is e.g. made of a photosensitive film and retained by an electromotive stage 213 as shown in FIG. 11B. The medium 212 designed for hologram is intermittently run in a direction of an arrow aa by drive of this electromotive stage 213.
As shown in FIG. 11A, the laser light L201 is emitted from laser light source 201 and incident on the half mirror 202. The laser light L201 is divided into the object light L202 and the reference light L203 by this half mirror 202.
The object light L202 is incident on the display apparatus 208 after traveling by way of the cylindrical lens 204 and collimator lens 205. The image is modulated, depending on an element image displayed when transmitted through this display apparatus 208. The modulated object light L202 is incident on the record medium designed for hologram 212 arranged at the exposing and recording section P201 after traveling by way of the projection lens 206 and the cylindrical lens 207. The reference light L203 is incident on the recording medium 212 designed for hologram arranged at the exposing and recording section P201, after traveling by way of an optical system of the cylindrical lens 209, the collimator lens 210 and the total reflection mirror 211.
Thus, interference fringes produced by interference between the reference light L203 and the object light L202 modulated by an image displayed by display apparatus 208 is sequentially exposed and recorded onto the hologram recording medium 212 as an element hologram in a striped or dotted manner.
The holographic stereogram produced by such holographic stereogram producing apparatus 200 is identified, with aggregate of pieces of the reference image information regarded as parts of each of element holograms, as two-dimensional image by an observer when the observer views the holographic stereogram with one of observer's both eyes from a certain position. The holographic stereogram produced thereby is identified, which is regarded aggregate of pieces of image information recorded as a part of each element hologram as the other two-dimensional image when an observer views the holographic stereogram with the other one of the observer's both eyes from any position except for the certain position. Thus, the holographic stereogram is identified, regarding an exposed and recorded image as a three-dimensional image owing to parallax effect between right and left eyes when an observer views the holographic stereogram with both his or her eyes.
An application as to such a holographic stereogram is e.g. stated in “Instant holographic portrait printing system” by Akira Shirakura, Nobuhiro Kihara and Shigeyuki Baba, in Proceeding of SPIE, Vol. 3293, pp.246–253, January 1998 and “High speed hologram portrait print system” by Kihara, Shirakura, and Baba disclosed in “Three-dimensional Image Conference 1998”, July, 1998 and so on. As stated therein, there is a printer system or the like constituted by combination of a imaging apparatus/image capture apparatus which captures an image of an object and produces a parallax image sequence and a printing apparatus such as the above-mentioned holographic stereogram producing apparatus 200 which outputs a holographic stereogram or a hologram as a print. Such a system can provide a service that encompasses from capturing an image of an object to printing the captured result at the same location.